In the Past, various known techniques for the measurement of hologram formation has been used, but these techniques are not suitable for normal silver-halide based photographic films since light forms a latent image in these films that is not revealed until development. However, photopolymer films and other recording media begin to form a hologram almost immediately upon exposure and consequently, it is possible to record a hologram with a laser of one color and to view its formation simultaneously with a second laser of another color. The color of the second laser or probe, is chosen so as to have no physical or chemical effect upon the recording medium. The two laser technique for photopolymer holograms is discussed in prior art publications. Similar techniques are also used in chemistry in which a holographic exposure illuminates a mixture, and the formation of a transient or permanent hologram gives a measure of chemical reactions. The two-laser technique can also be applied here as well as a single laser technique. These chemical applications are discussed in the prior art publications also.
Even in light of the prior art there is a need for a device that can be used in the study and characterization of holographic recording materials and films that utilize a single laser source.
Therefore, it is an object of this invention to provide a device that utilizes a single laser source in the study and characterization of holographic recording materials and films and a device that can be used in the control of holographic exposure systems to cause an optimum exposure to be produced.
Other advantages and objects of this invention will be obvious to those who are skilled in this art.